Looking at the Grand Canyon is like looking back in time. Forty million years ago, the Colorado River began cutting through the area. At the same time, the surrounding land was pushed up by forces deep within the earth. Rain, snow, ice, wind and plant roots rubbed away at the top of the new canyon. Below, the flowing river continued to uncover more and more levels of ancient rock.
Some of Earth's oldest rocks can be found here. There are many levels of granite, schist, limestone and sandstone.
SHIRLEY GRIFFITH: Three thousand years ago, American Indians occupied the Grand Canyon. Evidence of their existence has been found in many places. Bones, hair, feathers and the remains of plants have been found in deep, dry caves high in the rock walls.
The Hopi, the Paiute, the Navajo and other Native American tribes have all been in the area for at least seven centuries. However, much of what we know today about the Grand Canyon was recorded by John Wesley Powell. In eighteen sixty-nine, he became the first known white American to explore much of the canyon.
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JUNE SIMMS: Today, the Grand Canyon is known as one of the seven wonders of the natural world. About five million people visit the canyon each year. Most visitors walk along paths, part way down into the canyon. It takes several hours to walk to the bottom. It takes twice as long to get back up to the top. Some visitors ride mules to the bottom and back.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25